This invention relates in general to rear view devices. In particular, the invention relates to a rear view element folding device for a motor vehicle for approaching at least one pivot position of an element housing relative to an element foot that can be mounted on the motor vehicle, and for locking or unlocking at least one resting position of the element housing relative to the element foot. The invention further relates to a method for triggering such a rear view element folding device.
A drive folding mechanism for a rear view element is known from EP 2 439 106 B1, which is designed to be attached to a motor vehicle. This mechanism comprises a drive folding housing, which can be mounted between an element housing and an element foot that can be mounted on a motor vehicle. Further, a coupling member is provided which is brought into engagement with the element foot using a first spring means, wherein the coupling detent can be axially moved from a locking position and/or engagement position, in which coupling arresting elements hold back a relative rotation between the coupling member and the element foot in a form-fit manner, and an unlocking and/or non-engagement position, in which a friction engagement torque only somewhat holds back the relative rotation between the coupling member and the element foot around an element head axis, wherein the coupling member permits the element housing to be manually moved in relation to the element foot. Additionally, the mechanism comprises an electrical drive train for generating a relative rotation between the drive folding housing and the coupling member around the element head axis, wherein when the coupling member is in the non-engagement position and the electrical drive train generates a relative rotation between the drive folding housing and the coupling member, the drive folding housing rotations relative to the element foot until a drive stop surface of a drive stop means achieves a detent induces counter-torque, wherein the counter-torque is greater than the friction engagement torque, and thus stops the rotation of the drive folding housing in relation to the element foot, and instead causes the coupling member to rotation until the coupling member has reached an engaged position. The drive stop means is movably mounted on the drive folding housing, and the drive stop surface is engaged with the detent element mounted on the element foot, wherein the drive stop surface is biased axially towards the detent. The drive stop surface moves with the drive folding housing between:                a forward position, in which the drive folding housing and the element head are in a forward folding position;        a rearward position, in which the drive folding housing and the element head are in a rearward folding position; and        a drive position in which the drive folding housing and the element head are in an extended position, the coupling member is in the engagement position and the drive stop surface lies between the detent and the drive folding housing in order to provide a form-fit and repeatable stop.        
The known rear view element folding device uses a single motor for changing between the engagement position and the non-engagement position, i.e. for locking and unlocking, as well as for approaching the forward position, rearward position and drive position, i.e. for twisting, which leads to a complex structure.
The invention provides a rear view element folding device for a motor vehicle which has a simple structure, without reducing safety during locking. Large noise developments when approaching different positions of the rear view element should also be avoided. In addition, it should be possible to quickly approach any desired position.